1. Field of the Invention
The present invention relates to a blade server and more particularly, to a grounding spring plate for use in a ATCA blade server that can conveniently and detachably mounted in a track inside a case for ATCA blade server to secure and ground a computer motherboard blade.
2. Description of the Related Art
Currently, many enterprises install several tens or even several hundreds of mini servers to satisfy network traffic requirements. In order to improve further economic effect, blade servers are developed. A blade server is essentially a housing for a number of individual minimally-packaged computer motherboard “blades”, each including one or more processors, computer memory, computer storage, and computer network connections, but sharing the common power supply and air-cooling resources of the chassis. The idea is that by placing many blades in a single chassis, and then 19-inch rack-mounting them, systems can be more compact and powerful, but less expensive than traditional systems based on mainframes, or server farms of individual computers (see Blade server from Wikipedia).
The most attractive advantage of a blade server is its high reliability and extendibility. Every blade server has the backup function. The hot plugging of the server machine case that supports blade servers and system component parts provides high applicability. When one individual blade server failed, another blade server can take the place without interrupting the service of the system. When wishing to increase the processing power of the system, it needs only to insert more blade servers and to arrange these resources at the place where the demand is most strong.
Further, a case for ATCA blade server generally has multiple tracks mounted therein for the insertion of multiple computer motherboard blades. However, when inserting a computer motherboard blade into one track inside the case, the computer motherboard blade may vibrate and rub against the neighbor computer motherboard blade accidentally, thereby damaging motherboard or the related electronic component parts. After insertion of one computer motherboard blade into one track, screws are commonly used to affix the inserted computer motherboard blade to the respective track.
Further, a computer motherboard blade generally has a grounding spring member at one side for constituting with the case of the blade server a grounding loop. However, when mounting or dismounting a computer motherboard blade, the grounding spring member may be damaged or forced out of place accidentally.
FIGS. 11˜13 show a conventional design for securing a computer motherboard blade in a blade server. As illustrated, tracks B are fixedly mounted inside a metal case A for holding a respective computer motherboard blade A1. Each track B comprises two countersunk holes B2 on the front and rear ends for mounting, two parallel rails B1, and a metal guide C mounted in between the rails B1 for guiding the inserted computer motherboard blade A1 into position. The metal guide C comprises a plurality of clamping plates C1 symmetrically disposed at two sides, and a plurality of hooks C3 respectively extended from the clamping plates C1 at the bottom side. During installation, the metal guide C is inserted in between the rails B1 from the bottom side to force the locating holes C11 of each clamping plate C1 into engagement with a respective locating block B11 on the associating rail B1, and at the same time the hooks C3 are respectively hooked on the rails B1 at the bottom side. When one computer motherboard blade A1 is inserted into one track B inside the metal case A, the rails B1 and the clamping plates C1 of the metal guide C hold the inserted computer motherboard blade A1 in position. This computer motherboard blade mounting structure still has drawbacks as follows:
1. After mounting of the metal guide C in the track B, the base C2 of the metal guide C protrudes over the top surface of the track B. When inserting a computer motherboard blade A1 into the track B, the protruded base C2 of the metal guide C may hinder the insertion of the computer motherboard blade A1 or cause deformation of the inserted computer motherboard blade A1, or the inserted computer motherboard blade A1 may permanently deform the clamping plates C1 of the metal guide C.
2. When inserting one computer motherboard blade A1 into one track B, the bottom edge of the computer motherboard blade A1 is forced to rub against the surface of the base C2 of the metal guide C heavily. Further, the metal guide C has a plurality of holes C21 on its bottom panel that may hinder forward movement of the inserted computer motherboard blade A1 and cause damage to the inserted computer motherboard blade A1.
3. When the inserted computer motherboard blade A1 is set in position, the clamping plates C1 of the metal guide C are clamped on the computer motherboard blade A1 and electrically connect the grounding contacts of the computer motherboard blade A1 to the metal case A through the hooks C3, thereby constituting a grounding loop. The metal guide C is mounted on the track B, which is molded from plastics, and then kept in contact with the metal case A through the hooks C3. A dimensional error between the track B and the metal guide C or elastic fatigue of the hooks C3 for the inserted computer motherboard blade A1 may result in a contact error between the hooks C3 and the metal case A. Further, when repairing the metal guide C, the mechanic must remove the track B from the metal case A at first, and then remove the metal guide C from the track B for repair or replacement. After replacement or repair, the metal guide C must be mounted in the track B and then fastened with the track B to the inside of the metal case A again. This mounting and dismounting procedures are complicated.
FIGS. 14˜16 show another prior art design of guide track for use in a blade server for holding a computer motherboard blade. According to this design, the guide track D has a longitudinal sliding groove D1 for receiving a computer motherboard blade, ribs D2 symmetrically arranged at two sides of the longitudinal sliding groove D1, angled positioning portions D3 respectively extended from the ribs D2 for fastening to a metal case for blade server (not shown), and triangular spring plates D4 arranged along one side of the longitudinal sliding groove D1. When inserting a computer motherboard blade (not shown) into the longitudinal sliding groove D1, the inserted computer motherboard blade forces the triangular spring plates D4 outwards from the longitudinal sliding groove D1. After insertion of the computer motherboard blade, the triangular spring plates D4 are clamped on one side of the computer motherboard blade, thereby holding the computer motherboard blade in position. This design of guide track is still not satisfactory in function because of the following drawbacks:
1. When inserting a computer motherboard blade into the longitudinal sliding groove D1, the triangular spring plates D4 impart a pressure to one side of the computer motherboard blade. At this time, the protruding end of each triangular spring plate D4 may scratch the surface of the computer motherboard blade, leaving motherboard dust in the metal case of the blade server. Further, during movement of the computer motherboard blade into the longitudinal sliding groove D1, the bottom edge and one side of the computer motherboard blade opposite to the triangular spring plates D4 are heavily rubbed against the guide track D, producing a friction force that imparts a barrier to insertion of the computer motherboard blade.
2. The triangular spring plates D4 are arranged on one side of the longitudinal sliding groove D1 to give a pressure to the inserted computer motherboard blade from one side. Because the clamping force is not evenly applied to the inserted computer motherboard blade from two opposite sides, the clamping force is weak, and the computer motherboard blade may be forced out of place accidentally, causing shutdown of the computer motherboard blade or damage of storage data. Further, because of the uneven clamping force from the triangular spring plates D4 on the inserted computer motherboard blade, the triangular spring plates D4 may be damaged or deformed by the computer motherboard blade during insertion of the computer motherboard blade.
3. Further, the guide track D is fastened to the metal case of the blade server by means of its angled positioning portions D3. When the user touches one angled positioning portion D3 accidentally, the guide track D may be disconnected from the metal case of the blade server or forced out of position.
Therefore, it is desirable to provide a mounting structure for blade server that is easily detachable, holds the inserted computer motherboard blade positively in position, and assures positive grounding of the grounding terminal of the inserted computer motherboard blade.